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since i put on cobra speedster slashdowns, there is a fast idle at start and the bike takes a very long time to idle down. has anyone had this problem befor? and what can i do about it? just ordered s&s intake and PC V. any help would be greatly appreciated
 

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since i put on cobra speedster slashdowns, there is a fast idle at start and the bike takes a very long time to idle down. has anyone had this problem befor? and what can i do about it? just ordered s&s intake and PC V. any help would be greatly appreciated
OK one more time same answer.

I was told by the dealer about the fast idle when i picked up the bike, 3 miles on it stock. Man it some time shoots up to 1800 RPM, really annoying, scared the crap out of a mech at an independent shop:D , the S&S should have a position for the sensor to plug into, the BAK did, if you get rid of it there is no choke and it will run like crap until it warms up a bit, MOM says do not ride for up to 2 min on cold days after starting (RIGHT).

OH and mine also fast idles every time it is started even on a hot day, but calms down quickly.

Very irritating with pipes that set of car alarms but what can you do, would love to hear any suggestions that would work. I guess you could play with the idle screw and kick it up and then back down, but i am leary about turning it down to much because of oil flow, oil pump does not pump enough pressure below 900 RPMs and i have not installed a tach yet (note to self new item on MODS list )

Good luck and keep the shiny bits in the air.
 

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Mine does the exact same thing. Very annoying. It's as if the computer does not read the temp sensor right away. I wish someone would come up with a solution for this.
 

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I was glancing through the service manual and here is what it says

•Start the engine and warm it up thoroughly.
○At first the engine will run fast to decrease warm up time
(fast idle).
○Gradually the fast idle will lower to a certain RPM automatically.

So isnt this normal?
 

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yes it is normal.
 

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OK one more time same answer.

I was told by the dealer about the fast idle when i picked up the bike, 3 miles on it stock. Man it some time shoots up to 1800 RPM, really annoying, scared the crap out of a mech at an independent shop:D , the S&S should have a position for the sensor to plug into, the BAK did, if you get rid of it there is no choke and it will run like crap until it warms up a bit, MOM says do not ride for up to 2 min on cold days after starting (RIGHT).

OH and mine also fast idles every time it is started even on a hot day, but calms down quickly.

Very irritating with pipes that set of car alarms but what can you do, would love to hear any suggestions that would work. I guess you could play with the idle screw and kick it up and then back down, but i am leary about turning it down to much because of oil flow, oil pump does not pump enough pressure below 900 RPMs and i have not installed a tach yet (note to self new item on MODS list )

Good luck and keep the shiny bits in the air.
Bytehead, which sensor actually modulates the idle speed when the bike is first started? Any idea how the idle is increased? More air?
 

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I was glancing through the service manual and here is what it says

•Start the engine and warm it up thoroughly.
○At first the engine will run fast to decrease warm up time
(fast idle).
○Gradually the fast idle will lower to a certain RPM automatically.

So isnt this normal?
I agree with this being normal when the engine is cold. But after riding for a few hours in 80 deg weather, stop to fill up with gas, start bike and its reving like a raped ape. Its like using the choke on my carbed Roadstar when the motor is fully warmed up.

This is what doesn't make sense to me.
 

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I was glancing through the service manual and here is what it says

•Start the engine and warm it up thoroughly.
○At first the engine will run fast to decrease warm up time
(fast idle).
○Gradually the fast idle will lower to a certain RPM automatically.

So isnt this normal?
Yes the fast idle on the initial start up is normal. What I was referring to in my case, is if I shut the bike down for 10 minutes after it is warmed up and start it back up it will idle fast for about 20 seconds. I would think that since the engine is still warm at this point there should be no need for an increase in idle speed.
 

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Yes the fast idle on the initial start up is normal. What I was referring to in my case, is if I shut the bike down for 10 minutes after it is warmed up and start it back up it will idle fast for about 20 seconds. I would think that since the engine is still warm at this point there should be no need for an increase in idle speed.
Exactly the point I was trying to make!

Is there something the Kawi engineers considered important we're missing?
 

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Bytehead, which sensor actually modulates the idle speed when the bike is first started? Any idea how the idle is increased? More air?
Disclaimer: "Not a kawi rep or engineer just ask a lot of questions"

My limited understanding of the situation, is the little black plug that is in the air intake box (breather) is the cold air sensor, this is the little bugger that sets the idle to fast for up to two minutes when air temp is below 50. Then it is shut down when the engine temp sensor, signals the engine is warmed up the "choke" fast idle is shut off. The start routine in the ECU is Preset to start in fast idle, probably by the starter energizing, service manual is not specific, but i ask a lot of questions ;).

If you have ever started it, shut it off oops, and restarted it again the fast idle always kicks in whether it is 100 or 50, absolutely a pain in the ***(for the kiddies). I get lots of comments that start out "WTF :eek: that thing is idling way to fast" and then :confused: when it just slows down on its own.

The speed is increased the same way an old manual choke works, increases the fuel going to the engine, FI ya know, but instead of creating higher suction with a choke valve, just kicks the fuel flow up a touch. You can see the richness if you look at the pipes (not stock) and smell the rich fuel mix. And if you hold the throttle lightly you can feel the throttle move just a small amount.

From the service manual page 2-15 "○At first the engine will run fast to decrease warm up time (fast idle)"

So yup cannot do a thing about it, trying MAY damage the ECU, may not but why take the chance.

You have two options, like I did "get used to it, and get over it", or park it and walk (not an option, to much fun to ride).

Sorry to confirm the bad news but "HEY SCREW IT, LETS RIDE :D"

Oh and never assume,(insert an - after last s and u and think about it) that anything, that anyone else does, is logical or makes sense, someone must have thought this was a good idea, did not happen by mistake.

On a better news topic I (I.E. another poster steered me in the right direction) found a great solution for the ever present, left turn stuck in ****, problem but that is another post, ask if interested

Hope this helps, ride safe and keep the shiny bits in the air.
 

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Thats wierd. I just bought a new bike and i was annoyed at the fast idling after start up. But once i start riding and make stops for a break or a fill up, i dont have the fast idling anymore.

I guess then there is a issue.
 

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fast idle is normal. sometimes very fast idle! ;]]

the cold air sensor might not be the only 'factor'. when starting the engine cold, fast idle ensures a fast warmup and also a good oil pressure.
when starting warm, a fast idle makes sure the oil is pumped right away, w/o any delay...

that's why the manual suggests inspecting the idle: it has a lot to do w/ the oil pressure, etc..
 

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Thats wierd. I just bought a new bike and i was annoyed at the fast idling after start up. But once i start riding and make stops for a break or a fill up, i dont have the fast idling anymore.

I guess then there is a issue.
Ok some info please, stock? Mods?
With stock pipes you may not notice the idle increase after riding as it is not as aggrevasive as the cold idle.
With stock pipes I could barely tell my bike was running, tryed to start it several times while running :eek:

+1 for

that's why the manual suggests inspecting the idle: it has a lot to do w/ the oil pressure, etc..
This could be an issue, have you adjusted the idle, up or down

Many people, myself included, adjust the idle down to try to get the lopping sound, but too low can cause many problems.

If all else fails, it is new? correct, take it back to the dealer (cool get to ride) and with head held humbley ask if they would adjust the idle.

Ride safe and let us know.
 

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you will have to let us know how long that no mods thing works out for you lol. I had my bike painted within the first week I owned it along with a few other things but I guess i just wanted it to be "mine" but if you don't mod good for you more money in the bank, I know the wife would be happier if I stoped moding
 

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Discussion Starter #16
Well getting s&s intake and power comander V on friday. the mech said this will help with the excesive fast idle time.
 

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Is this only occuring when the ambient temperature is low or are the folks in Florida experiencing the same thing? I asked the couple of guys I know here in Thailand that have 900's if they have an excessively fast idle issue and they both said "no". I believe we have a different ECM than Stateside units.
 

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David : I am not a big fan of modding the bike for the sake of doing it. I love the stock look and feel. All i did was add a backrest and a luggage rack. Contemplating saddle bags and a different handlebar for comfort and that will be it. :)
 

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you will have to let us know how long that no mods thing works out for you lol. I had my bike painted within the first week I owned it along with a few other things but I guess i just wanted it to be "mine" but if you don't mod good for you more money in the bank, I know the wife would be happier if I stoped moding
+100000000 :)
 

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I have owned two nines.....both needed at least 1 minute plus to come off fast idle. It usually goes like this:
1.Start bike.
2.Fast idle....hear click....idle goes down.
3. Slightly lower idle.....hear second click...idle goes to normal.
I have gotten used to putting on my helmet and gloves etc....AFTER I start my bike...lol.
 
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